Ibn Tamim narrated on the authority of his uncle ('Abdullah b. Zaid) that the Messenger of Allah ﷺ went out to the place of prayer and prayed for rain and faced towards Qibla, and turned round his mantle and prayed two rak'ahs. (Using translation from Muslim 894b)   

أَنَّ النَّبِيَّ ﷺ خَرَجَ إِلَى الْمُصَلَّى «يَسْتَسْقِي فَاسْتَقْبَلَ الْقِبْلَةَ وَقَلَبَ رِدَاءَهُ وَصَلَّى رَكْعَتَيْنِ»  

His father said: "I asked Ibn 'Abbas how the Messenger of Allah ﷺ prayed for rain. He said: 'The Messenger of Allah ﷺ went out (dressed) in a state of humility, beseeching and humble. He sat on the minbar but he did not deliver a Khutbah like this Khutbah of yours, rather he kept supplicating, beseeching and saying the takbir, and he prayed two rak'ahs as he used to do during the two 'Eids.'" (Using translation from Nasāʾī 1508)  

عَنْ صَلَاةِ رَسُولِ اللهِ ﷺ فِي الِاسْتِسْقَاءِ فَقَالَ «خَرَجَ رَسُولُ اللهِ ﷺ مُتَبَذِّلًا مُتَوَاضِعًا مُتَضَرِّعًا فَجَلَسَ عَلَى الْمِنْبَرِ فَلَمْ يَخْطُبْ خُطْبَتَكُمْ هَذِهِ لَكُنْ لَمْ يَزَلْ فِي الدُّعَاءِ وَالتَّضَرُّعِ وَالتَّكْبِيرِ وَصَلَّى رَكْعَتَيْنِ كَمَا كَانَ يُصَلِّي فِي الْعِيدِ»  

His father said: "So and so sent me to ask him how the Messenger of Allah ﷺ prayed for rain (Istisqa')." He said: 'The Messenger of Allah ﷺ went out beseeching and humble, (dressed) in a state of humility. He did not give a Khutbah like this Khutbah of yours, and he prayed two rak'ahs.'" (Using translation from Nasāʾī 1506)  

عَنْ صَلَاةِ رَسُولِ اللهِ ﷺ فِي الِاسْتِسْقَاءِ فَقَالَ «خَرَجَ رَسُولُ اللهِ ﷺ مُتَضَرِّعًا مُتَوَاضِعًا مُتَبَذِّلًا فَلَمْ يَخْطُبْ نَحْوَ خُطْبَتِكُمْ هَذِهِ وَصَلَّى رَكْعَتَيْنِ»  

The Messenger of Allah ﷺ prayed for rain wearing a black khamisah. (Using translation from Nasāʾī 1507)  

أَنَّ رَسُولَ اللهِ ﷺ «اسْتَسْقَى وَعَلَيْهِ خَمِيصَةٌ سَوْدَاءُ»